The present invention relates to isolation of vibration and/or shock, more particularly to passive isolation implementing resilient (e.g., elastomeric) material.
In military and commercial contexts, various methods and devices have been known for effecting passive vibration isolation and/or passive shock isolation. Such methods and devices are commonly practiced in association with low natural frequency hardware (e.g., machinery) in order to isolate vibrations at relatively low natural frequencies. Vibration isolation mounts have been developed that seek to address low frequency requirements for vibration and/or shock. However, generally speaking, conventional isolation mounts have not been entirely satisfactory, in terms of their natural frequency response, for purposes of either controlling unwanted vibrations or reducing acoustic energy propagation.
Among the practical considerations for vibration/shock mounts is the desirability of reducing cost and increasing efficiency of fabricating the mount. Many conventional approaches to vibration/shock isolation implement a main elastomeric body. Fabrication of the conventional mount usually involves either (i) a single-part, single-step molding process of the elastomer and the metal structure, or (ii) a two-part, two-step molding process of the elastomer and the metal structure. One-part molding fabrication tends to be performed more often for making smaller mounts, whereas two-part molding fabrication tends to be performed more often for making larger mounts, or for pipe hanger/pipe mount applications.
Another practical consideration for vibration/shock mounts is the desirability of reducing the “footprint” (synonymously referred to herein as the “envelope”) of the mount. A “snubber” (synonymously referred to herein as a “restraint” or “restrainer”) is an isolator component that limits displacement of the isolator, for instance in the vertical or horizontal direction. Some conventional mounts utilize a snubber that is situated inside the envelope/footprint of the mount; nevertheless, many other conventional mounts utilize a snubber that is situated outside the envelope/footprint of the mount, thereby effectively enlarging the envelope/footprint of the mount.